Give the reason for bleaching action of Cl2.
When chlorine reacts with water, it produces nascent oxygen. This nascent oxygen then combines with the coloured substances present in the organic matter to oxide them into colourless substances.
Cl2 + H2O → 2HCl + [O]
Coloured substances + [O] → Oxidized colourless substance
Why is helium used in diving apparatus?
Why are pentahalides more covalent than trihalides?
Give the formula and describe the structure of a noble gas species which is isostructural with:
(i) ICl-4
(ii) IBr-2
(iii) BrO-3
Why is H2O a liquid and H2S a gas?
How is O3 estimated quantitatively?
What happens when sulphur dioxide is passed through an aqueous solution of Fe(III) salt?
Why is BiH3 the strongest reducing agent amongst all the hydrides of Group 15 elements?
Why are halogens strong oxidising agents?
Arrange the following in the order of property indicated for each set:
(i) F2, Cl2, Br2, I2- increasing bond dissociation enthalpy.
(ii) HF, HCl, HBr, HI - increasing acid strength.
(iii) NH3, PH3, AsH3, SbH3, BiH3- increasing base strength.
Comment on the nature of two S-O bonds formed in SO2 molecule. Are the two S-O bonds in this molecule equal?
For the reaction R → P, the concentration of a reactant changes from 0.03 M to 0.02 M in 25 minutes. Calculate the average rate of reaction using units of time both in minutes and seconds.
Write the formulas for the following coordination compounds:
(i) Tetraamminediaquacobalt (III) chloride
(ii) Potassium tetracyanonickelate(II)
(iii) Tris(ethane-1,2-diamine) chromium(III) chloride
(iv) Amminebromidochloridonitrito-N-platinate(II)
(v) Dichloridobis(ethane-1,2-diamine)platinum(IV) nitrate
(vi) Iron(III) hexacyanoferrate(II)
(i) Write structures of different isomeric amines corresponding to the molecular formula, C4H11N
(ii) Write IUPAC names of all the isomers.
(iii) What type of isomerism is exhibited by different pairs of amines?
Why are solids rigid?
Write any two characteristics of Chemisorption.
Write the structures of the following compounds.
(i) α-Methoxypropionaldehyde
(ii) 3-Hydroxybutanal
(iii) 2-Hydroxycyclopentane carbaldehyde
(iv) 4-Oxopentanal
(v) Di-sec-butyl ketone
(vi) 4-Fluoroacetophenone
Which of the ores mentioned in Table 6.1 can be concentrated by magnetic separation method?
Silver atom has completely filled d orbitals (4d10) in its ground state. How can you say that it is a transition element?
Glucose or sucrose are soluble in water but cyclohexane or benzene (simple six membered ring compounds) are insoluble in water. Explain.
Write structures of the following compounds:
(i) 2-Chloro-3-methylpentane
(ii) 1-Chloro-4-ethylcyclohexane
(iii) 4-tert. Butyl-3-iodoheptane
(iv) 1,4-Dibromobut-2-ene
(v) 1-Bromo-4-sec. butyl-2-methylbenzene
Write the IUPAC names of the following coordination compounds:
(i) [Co(NH3)6]Cl3
(ii) [Co(NH3)5Cl]Cl2
(iii) K3[Fe(CN)6]
(iv) K3[Fe(C2O4)3]
(v) K2[PdCl4]
(vi) [Pt(NH3)2Cl(NH2CH3)]Cl
Classify the following amines as primary, secondary or tertiary:
(i)
(ii)
(iii) (C2H5)2CHNH2
(iv) (C2H5)2NH
In the series Sc (Z = 21) to Zn (Z = 30), the enthalpy of atomization of zinc is the lowest, i.e., 126 kJ mol−1. Why?
Why is sulphuric acid not used during the reaction of alcohols with KI?
With reference to which classification has the statement, ranitidine is an antacid been given?
Identify allylic alcohols in the above examples.
How are polymers classified on the basis of structure?
What are the expected products of hydrolysis of lactose?
Why is the ester hydrolysis slow in the beginning and becomes faster after sometime?
Calculate the emf of the cell in which the following reaction takes place:
Ni(s) + 2Ag+ (0.002 M) → Ni2+ (0.160 M) + 2Ag(s)
Given that Eøcell = 1.05 V
Its more effective due to the presence of water molecules. As more moles of water is used, more nascent oxygen is produced, and hence more colored substances gets oxidised and lose their color.
So is the bleaching effective due to the presence of water or oxygen?